// https://syzkaller.appspot.com/bug?id=71d4f87700130c18f50b690ce4489bd52b214a4c
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/loop.h>

#ifndef __NR_memfd_create
#define __NR_memfd_create 319
#endif

static unsigned long long procid;

static void sleep_ms(uint64_t ms)
{
  usleep(ms * 1000);
}

static uint64_t current_time_ms(void)
{
  struct timespec ts;
  if (clock_gettime(CLOCK_MONOTONIC, &ts))
    exit(1);
  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

static void use_temporary_dir(void)
{
  char tmpdir_template[] = "./syzkaller.XXXXXX";
  char* tmpdir = mkdtemp(tmpdir_template);
  if (!tmpdir)
    exit(1);
  if (chmod(tmpdir, 0777))
    exit(1);
  if (chdir(tmpdir))
    exit(1);
}

static bool write_file(const char* file, const char* what, ...)
{
  char buf[1024];
  va_list args;
  va_start(args, what);
  vsnprintf(buf, sizeof(buf), what, args);
  va_end(args);
  buf[sizeof(buf) - 1] = 0;
  int len = strlen(buf);
  int fd = open(file, O_WRONLY | O_CLOEXEC);
  if (fd == -1)
    return false;
  if (write(fd, buf, len) != len) {
    int err = errno;
    close(fd);
    errno = err;
    return false;
  }
  close(fd);
  return true;
}

struct fs_image_segment {
  void* data;
  uintptr_t size;
  uintptr_t offset;
};

#define IMAGE_MAX_SEGMENTS 4096
#define IMAGE_MAX_SIZE (129 << 20)

static unsigned long fs_image_segment_check(unsigned long size,
                                            unsigned long nsegs,
                                            struct fs_image_segment* segs)
{
  if (nsegs > IMAGE_MAX_SEGMENTS)
    nsegs = IMAGE_MAX_SEGMENTS;
  for (size_t i = 0; i < nsegs; i++) {
    if (segs[i].size > IMAGE_MAX_SIZE)
      segs[i].size = IMAGE_MAX_SIZE;
    segs[i].offset %= IMAGE_MAX_SIZE;
    if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size)
      segs[i].offset = IMAGE_MAX_SIZE - segs[i].size;
    if (size < segs[i].offset + segs[i].offset)
      size = segs[i].offset + segs[i].offset;
  }
  if (size > IMAGE_MAX_SIZE)
    size = IMAGE_MAX_SIZE;
  return size;
}
static int setup_loop_device(long unsigned size, long unsigned nsegs,
                             struct fs_image_segment* segs,
                             const char* loopname, int* memfd_p, int* loopfd_p)
{
  int err = 0, loopfd = -1;
  size = fs_image_segment_check(size, nsegs, segs);
  int memfd = syscall(__NR_memfd_create, "syzkaller", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (ftruncate(memfd, size)) {
    err = errno;
    goto error_close_memfd;
  }
  for (size_t i = 0; i < nsegs; i++) {
    if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) {
    }
  }
  loopfd = open(loopname, O_RDWR);
  if (loopfd == -1) {
    err = errno;
    goto error_close_memfd;
  }
  if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
    if (errno != EBUSY) {
      err = errno;
      goto error_close_loop;
    }
    ioctl(loopfd, LOOP_CLR_FD, 0);
    usleep(1000);
    if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
      err = errno;
      goto error_close_loop;
    }
  }
  *memfd_p = memfd;
  *loopfd_p = loopfd;
  return 0;

error_close_loop:
  close(loopfd);
error_close_memfd:
  close(memfd);
error:
  errno = err;
  return -1;
}

static long syz_mount_image(volatile long fsarg, volatile long dir,
                            volatile unsigned long size,
                            volatile unsigned long nsegs,
                            volatile long segments, volatile long flags,
                            volatile long optsarg)
{
  struct fs_image_segment* segs = (struct fs_image_segment*)segments;
  int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs;
  char* mount_opts = (char*)optsarg;
  char* target = (char*)dir;
  char* fs = (char*)fsarg;
  char* source = NULL;
  char loopname[64];
  if (need_loop_device) {
    memset(loopname, 0, sizeof(loopname));
    snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid);
    if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1)
      return -1;
    source = loopname;
  }
  mkdir(target, 0777);
  char opts[256];
  memset(opts, 0, sizeof(opts));
  if (strlen(mount_opts) > (sizeof(opts) - 32)) {
  }
  strncpy(opts, mount_opts, sizeof(opts) - 32);
  if (strcmp(fs, "iso9660") == 0) {
    flags |= MS_RDONLY;
  } else if (strncmp(fs, "ext", 3) == 0) {
    if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0)
      strcat(opts, ",errors=continue");
  } else if (strcmp(fs, "xfs") == 0) {
    strcat(opts, ",nouuid");
  }
  res = mount(source, target, fs, flags, opts);
  if (res == -1) {
    err = errno;
    goto error_clear_loop;
  }
  res = open(target, O_RDONLY | O_DIRECTORY);
  if (res == -1) {
    err = errno;
  }

error_clear_loop:
  if (need_loop_device) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
    close(memfd);
  }
  errno = err;
  return res;
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  int iter = 0;
  DIR* dp = 0;
retry:
  while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
  }
  dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EMFILE) {
      exit(1);
    }
    exit(1);
  }
  struct dirent* ep = 0;
  while ((ep = readdir(dp))) {
    if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0)
      continue;
    char filename[FILENAME_MAX];
    snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
    while (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
    }
    struct stat st;
    if (lstat(filename, &st))
      exit(1);
    if (S_ISDIR(st.st_mode)) {
      remove_dir(filename);
      continue;
    }
    int i;
    for (i = 0;; i++) {
      if (unlink(filename) == 0)
        break;
      if (errno == EPERM) {
        int fd = open(filename, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno != EBUSY || i > 100)
        exit(1);
      if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW))
        exit(1);
    }
  }
  closedir(dp);
  for (int i = 0;; i++) {
    if (rmdir(dir) == 0)
      break;
    if (i < 100) {
      if (errno == EPERM) {
        int fd = open(dir, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno == EBUSY) {
        if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW))
          exit(1);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    exit(1);
  }
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  for (int i = 0; i < 100; i++) {
    if (waitpid(-1, status, WNOHANG | __WALL) == pid)
      return;
    usleep(1000);
  }
  DIR* dir = opendir("/sys/fs/fuse/connections");
  if (dir) {
    for (;;) {
      struct dirent* ent = readdir(dir);
      if (!ent)
        break;
      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
        continue;
      char abort[300];
      snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
               ent->d_name);
      int fd = open(abort, O_WRONLY);
      if (fd == -1) {
        continue;
      }
      if (write(fd, abort, 1) < 0) {
      }
      close(fd);
    }
    closedir(dir);
  } else {
  }
  while (waitpid(-1, status, __WALL) != pid) {
  }
}

static void reset_loop()
{
  char buf[64];
  snprintf(buf, sizeof(buf), "/dev/loop%llu", procid);
  int loopfd = open(buf, O_RDWR);
  if (loopfd != -1) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
  }
}

static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  write_file("/proc/self/oom_score_adj", "1000");
  if (symlink("/dev/binderfs", "./binderfs")) {
  }
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter = 0;
  for (;; iter++) {
    char cwdbuf[32];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      exit(1);
    reset_loop();
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      if (chdir(cwdbuf))
        exit(1);
      setup_test();
      execute_one();
      exit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      sleep_ms(1);
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

void execute_one(void)
{
  memcpy((void*)0x20000000, "reiserfs\000", 9);
  memcpy((void*)0x20000340, "./file0\000", 8);
  *(uint64_t*)0x20000040 = 0x20010000;
  memcpy(
      (void*)0x20010000,
      "\x00\x40\x00\x00\x68\x02\x00\x00\x97\x3d\x00\x00\x12\x00\x00\x00\x00\x00"
      "\x00\x00\x84\x3d\x00\x00\x00\x04\x00\x00\x73\x56\x4d\x38\x84\x03\x00\x00"
      "\x1e\x00\x00\x00\x00\x00\x27\xd0\x00\x10\xcc\x03\x02\x00\x01\x00\x52\x65"
      "\x49\x73\x45\x72\x33\x46\x73\x00\x00\x00\x03\x00\x00\x00\x02",
      69);
  *(uint64_t*)0x20000048 = 0x45;
  *(uint64_t*)0x20000050 = 0x2000;
  *(uint64_t*)0x20000058 = 0x200000c0;
  memcpy((void*)0x200000c0,
         "\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\xed\x15\x00\x00\x00\x00"
         "\x1e\x00\x00\x84\x3d\x00\x00\x00\x04\x00\x00\x73\x56\x4d\x38\x84\x03",
         34);
  *(uint64_t*)0x20000060 = 0x22;
  *(uint64_t*)0x20000068 = 0x3d96000;
  *(uint64_t*)0x20000070 = 0x20000380;
  memcpy(
      (void*)0x20000380,
      "\x01\x00\x02\x00\x5c\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x00\x00\x00\x00\x00\x2c\x00\xd4\x0f\x01\x00\x01\x00\x00\x00\x03\x00"
      "\x00\x00\x01\x00\x00\x00\xf4\x01\x00\x00\x02\x00\x30\x00\xa4\x0f\x67\x16"
      "\x8d\xcf\x59\xe2\xa3\x0f\x34\xca\x7d\xbd\xee\xf6\xd7\xe1\x96\xbc\xd8\x4e"
      "\xf9\xbb\xf9\xb4\xb8\x7f\x37\xd0\x00\x04\x00\x00\x00\x00\x00\x00\x2c\x61"
      "\x61\x42\x36\x8f\xe8\x61\xa6\x6c\x82\x41\xd7\x10\x65\x30\x95\x61\xda\xe8"
      "\xbb\x41\xca\x66\x82\x96\x16\x44\x9e\xb0\x08\x34\xaf\x7a\xfe\x5a\xb1\x80"
      "\xb4\x3e\xd5\x8e\x77\x52\x7a\xf6\xd1\xcd\xaf\x6f\x8c\xd6\x02\xcd\x3f\x51"
      "\x74\x73\x82\xdd\x26\x97\x4c\xca\x81\xf5\x22\x19\xfa\x3e\x4f\xe9\xa4\xa5"
      "\x42\x1a\xb3\x1d\xcb\x4d\xbe\x43\xa7\x3a\x23\x12\xee\xd4\xd0\xa8\x6f\x19"
      "\x8a\x06\x99\x7f\xa2\xc6\x54\x25\x31\x16\x8b\xd4\xa7\xff\xc9\xd0\xfc\x02"
      "\x29\x37\xdd\x38\x01\xa0\x2d\xf8\xc7\x1d\xc7\x47\x19\xe6\x54\xa5\x7d\x79"
      "\x6f\x05\x6c\x09\xb2\xc0\x92\x8f\x3d\x4e\x47\x0d\x81\x5d\x42\x6b\x22\x15"
      "\x7b\x48\x11\xfd\xe0\x4a\x28\xdf\x44\x4b\x97\xa1\xd4\xcf\x3f\xcf\x4f\x96"
      "\x50\x58\xe1\x3b\xd6\xa9\xb5\xda\x66\x9b\x06\xd2\xbd\x50\x67\xc3\xe2\x37"
      "\x5a\x3c\xc8\x29\xd9\x79\x77\xcc\xdc\x52\xd6\x2b\xb2\xf8\x53\xb6\x73\x3e"
      "\x54\x67\xe9\xf3\x95\x2c\x81\x7a",
      314);
  *(uint64_t*)0x20000078 = 0x13a;
  *(uint64_t*)0x20000080 = 0x3d97000;
  *(uint64_t*)0x20000088 = 0x20000140;
  memcpy((void*)0x20000140,
         "\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x28"
         "\x00\x04\x00\x02\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x20\x00"
         "\x04\x00\x2e\x2e\x00\x00\x00\x00\x00\x00\x2e\x00\x00\x00\x00\x00\x00"
         "\x00\xed\x41\x00\x00\x03\x44\x4e\x3e\x03",
         61);
  *(uint64_t*)0x20000090 = 0x3d;
  *(uint64_t*)0x20000098 = 0x3d97fa0;
  syz_mount_image(0x20000000, 0x20000340, 0, 4, 0x20000040, 0x208403,
                  0x20000580);
  memcpy((void*)0x20000540, "cramfs\000", 7);
  memcpy((void*)0x20000180, "./file0\000", 8);
  syz_mount_image(0x20000540, 0x20000180, 0, 0, 0, 0x240038, 0x20001ec0);
  memcpy((void*)0x20000540, "cramfs\000", 7);
  memcpy((void*)0x20000180, "./file0\000", 8);
  syz_mount_image(0x20000540, 0x20000180, 0, 0, 0, 0x240038, 0x20001ec0);
}
int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  use_temporary_dir();
  loop();
  return 0;
}